RPL WRRDC’S RIPARIAN LANDSRP MANAGEMENT NEWSLETTER A COMPONENTia OF THE RIVER RESTORATION AND MANAGEMENT PROGRAM

Managing snags and large woody debris MANAGING Snags and large woody debris (LWD) are the sticks, branches, trunks and whole trees that fall into rivers snags and and streams. LWD is important in streams and rivers from both an ecological and a geomorphic/hydraulic viewpoint. LWD provides important in-stream habitat arge oody for aquatic animals, as well as stable sites for the processing of carbon and nutrients.Through its impact LW on channel structure and flow, LWD also assists in the ebris formation of habitat (such as scour pools). This latter D process has led to the misguided belief that LWD also causes significant channel erosion. Another false belief is that snags significantly reduce channel capacity, leading to overflowing of banks during flood events. These misunderstandings about the effects of LWD on erosion and flooding, has meant that snag removal programs have continued throughout Australia, even after the initial rationale for snag removal (safer river transport) had ceased to be relevant.The problems that exist in managing large woody debris are, therefore, not so much its negative impact, but the long and widely- held perceptions of its impact.

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EDITION 16, 2000 CONtents Theme: Managing snags and Large Woody Debris 1 and 3 Research notes 1: The importance of large woody debris surfaces for algal growth in lowland rivers 6 Getting a Grip: Resnagging the River Murray 9 This publication is managed by Research notes 2: Some observations on the amount and the Land and Water Resources distribution of large woody debris in Australian streams 12 Research and Development The riparian adventures of Eco-man and Dr Earth 18 Corporation (LWRRDC), GPO Box 2182, Canberra It’s a Wrap: News from around Australia 21 ACT 2601

LWRRDC’s mission is to provide national leadership in utilising R&D to improve the long-term productive capacity, sustainable use, management and conservation of Australia’s land, water and vegetation resources. The Corporation will establish directed, integrated and focused programs where there is clear RIP rian lands: justification for additional public WHERE LAND AND WATER MEET funding to expand or enhance a the contribution of R&D to From the Editor sustainable management April 2000 already (!) and the Riparian Lands Program Phase One is of natural resources. wrapping up in time for Phase Two to begin in June 2000. I am pleased to LWRRDC’s Home Page is: announce that I have been appointed as the Program Coordinator for www.lwrrdc.gov.au Phase Two, with Phil Price also working with me in this role over the next five years.We are thrilled to be able to continue working on a program that Edition 16, April 2000 is committed to integrating science and practical experience in ways that RipRap is published four times a promote and assist the improved management of rivers and riparian lands year. Contributions and comments across Australia. Negotiations are now underway with many different are welcomed and should be groups about the priorities for investment, and opportunities for partner- addressed to the Editor. ship in Phase Two of the Program. Before we can move into Phase Two, however, there remains a great Editor: Dr Siwan Lovett deal of work to be done in Phase One. The next few months will be spent ensuring that the results of the research undertaken in Phase One are Feedback and comments to: converted into useful and relevant products for a range of different end- Dr Siwan Lovett LWRRDC Program Coordinator users. One of these products is RipRap,with this edition focusing on the River Restoration issue of snag and large woody debris management. This topic was and Riparian Lands requested by quite a few readers, and we have tracked down the most LWRRDC, GPO Box 2182 recent research being undertaken across the country and combined it with Canberra ACT 2601 information from the Riparian Land Tel: 02 6257 3379 Management Technical Guidelines Fax: 02 6257 3420 to provide a good overview of the Email: [email protected] management and R&D issues. I Website: www.rivers.gov.au hope you enjoy this edition and, in particular, the cartoon that is Designed by: Angel Ink thinking laterally about ways to Printed by: Goanna Print better manage our riparian lands!!! ISSN 1324-6941

2 THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION MANAGING snags and arge oody ebris continued from page 1 L WD Extract from Simon Treadwell (ed.), 1999, ‘Managing snags and large woody debris’ in WHY IS LWD IMPORTANT? S. Lovett and P. Price (eds), Riparian Land Management Technical Guidelines, Volume two: LWD is very significant in the ecology of On-ground Management Tools and Techniques, Land and Water Resources Research and streams and, by reason of the linkages between Development Corporation, Canberra, pp. 15–22. water and land, in other ecosystems. It is now apparent that de-snagging has had a Large woody debris as habitat for fish significant negative environmental impact on Woody debris provides important habitat for stream ecosystems. Major effects include the direct use by a number of aquatic and terrestrial loss of habitat for fish and other aquatic and organisms. Such uses include shelter from high terrestrial organisms, to the point where some current velocities, shade, feeding sites, spawning native species are threatened or locally extinct. sites, nursery areas for larvae and juvenile fish, The removal of snags has also had a significant territory markers and refuge from predation. impact on channel morphology. De-snagged Snags are most effective as habitat if they have a rivers typically become uniform drainage complex structure providing a number of channels, with fewer channel features such as different-sized spaces, including hollows within scour holes and bars that retain, or act as the debris piece and spaces between branches. substrates for the processing of carbon and Branches extending into the water column and nutrients by instream organisms. Furthermore, above the water surface provide habitat at the extensive research on the hydraulic effects of different water levels required by different fish snags has indicated that snags, especially in species. Single large trees that fall into a river can large rivers, have little adverse impact on often provide the full range of complex spaces channel capacity and snag removal does little required. to reduce the height of major floods. The challenge in achieving ‘best practice’ LWD management lies in maximising the Snags as habitat for other organisms positive contribution of LWD in both of its In general, the types of snags that provide major roles; including, where appropriate, the habitat for fish also provide habitat for other restoration of snags in de-snagged rivers. aquatic and terrestrial organisms. Submerged Fortunately, this challenge has been made wood, with a complex surface structure of easier by recent research that confirms the real grooves, splits and hollows, provides space for (as opposed to the perceived) impact of LWD colonisation by a range of invertebrates, on streams, rivers and riparian land (see later microbes and algae. Some invertebrates feed articles in RipRap for details). directly on the wood while others graze the biofilm (that is, the combined microbe and algal community). The species composition within the biofilm community depends on the position of the wood substrate within the water column. The shallower the water in which the substrate occurs, the higher the density of algal species compared with substrate located deeper in the water column where light does not reach. Species composition of both biofilm and inver- tebrates also depends on the substrate type. Willows and other introduced tree species appear to have a less diverse invertebrate community compared with native/indigenous tree species. Similarly, community composition Natural snags provide a range of habitat types suitable for fish and other aquatic and terrestrial organisms, Ovens River, varies according to the type of substrate (for Victoria. Photo by Simon Treadwell. example, wood compared with concrete pipes).

THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION 3 MANAGING snags andLW arge oody D ebris Birds, reptiles and mammals also use woody of food for invertebrates and fish. The algal debris for resting, foraging and lookout sites. component of biofilm may also produce a signif- Birds commonly use the exposed branches of icant amount of carbon and, hence, food through snags as perch sites, while turtles often climb out photosynthesis. Many invertebrate species and of the water using snag surfaces. Snags spanning some fish eat the algae that are growing on wood the channel may also be used by mammals and surfaces. In sandy, turbid rivers where woody reptiles as stream crossing points. Many aquatic substrate may be the only hard substrate avail- invertebrates have a terrestrial adult stage and able for colonisation, or in rivers that have been require snags extending above the water surface isolated from floodplain carbon inputs by river to provide sites for emergence from their larval regulation and clearing, most of the food for to adult stages. aquatic animals is found on snags. In upland streams, debris dams (large accumulations of woody debris that often span Snags as sites for carbon the entire channel) retain large amounts of and nutrient processing particulate organic material. This material Another important, but often overlooked decomposes into smaller pieces and is then function of snags is their role in carbon and transported downstream. (As stream size Above: Channel habitat formed by nutrient processing. Snags provide important increases, large debris dams become less snags parallel to flow, Warren River, substrate for the development of biofilms. The common and the ability of woody debris to retain Western Australia. Photo by Simon bacterial and fungal components of biofilm these small particles may decrease.) However, Treadwell. contribute to the decomposition of the woody retention of organic material and stabilisation of Below: Channel habitat formed by substrate and, hence, to the supply of dissolved sandy substrate by snags may still be significant snags perpendicular to flow, Kiewa and particulate organic material (carbon) to the in lowland rivers. Water flowing over snags also River, Victoria. Photo by Chris Gippel. water column. Organic matter is a major source helps to re-oxygenate that water and prevent stagnation that can cause fish deaths, odours and other water quality problems.

The role of snags in habitat formation As well as providing habitat for a range of aquatic and terrestrial species, snags also contribute to the development of other habitat types by their impact on channel structure. The main types of habitat formed by snags depend on snag orientation and stream power (see Table 1). Scour pools formed by snags spanning the channel are particularly important for wildlife, especially in streams with low or no summer flow. When flow ceases, these pools provide the only habitat available for aquatic species, and are a source of recruitment for re-colonisation when normal flow returns.

Table 1: Habitat development as determined by snag orientation.

Orientation to flow Habitat formed Upstream Downstream Parallel Scour pool Bar/island Angled Combination Combination pool/bar pool/bar Perpendicular – on bed Depositional zone Scour pool – above bed Scour pool Scour pool

4 THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION MANAGING snags andLD argeW oody ebris Stream power is an important determinant of whether snags influence habitat development. In summary Stream power is a function of gradient and Snags and LWD are important for all the reasons discussed so far. The discharge and often peaks in middle reaches overall management objective should be where high flows and high gradients occur. In lowland reaches, stream power typically declines To manage snags and large woody because of the decrease in stream gradient, even though total discharge may increase. Where stream power is high (in middle reaches and in debris in such a way that the ecological some tropical streams with high cyclonic discharge), snags will tend to be flushed out of health of the river is enhanced at the the main channel and deposited along the banks or downstream where stream power is lower. same time that risks of flooding and

The role of snags in erosion streambank erosion are diminished. In particular situations, snags may contribute to In attempting to realise this management objective, several ‘critical factors’ some erosion of banks. However, similar patterns need to be considered — these are outlined below. If you want more infor- of erosion can also be found in de-snagged mation about each of these critical factors, check out Guideline B in rivers, so removal of snags will not necessarily Volume 2, and Chapter 7 in Volume 1 of the Riparian Lands Management prevent bank erosion. Snags help to stabilise the Technical Guidelines. bed, and there are many instances recorded where removal of snags has resulted in severe degradation of the channel bed and, eventually, the banks. CRITICAL factors A river channel needs to be substantially blocked by LWD before there is a significant I. Critical factors for managing existing snags effect on the movement of floodwaters. Only The actual contribution of snags to flooding and erosion LWD which is large (that is, it covers more than ~ Are snags the actual cause of observed problems? 10% of the channel cross section) and is oriented ~ Determine hydraulic effect of constructions/impoundments across (perpendicular to) the direction of water on flooding elsewhere in the river flow causes substantial local water level ~ Determine if bank erosion is caused by other factors increases, and increases the chance of water (for example, channel instability) overflowing stream banks during flood flows. II. Critical factors for managing snag restoration Smaller items have little or no impact on local water levels. LWD has the least effect on water ~ Loads flow when it is aligned with the flow (at ~Types and structure of material 140–180° to the direction of water flow), is ~ Sources ~Position in channel located on the channel margins or in other areas ~Orientation of low flow velocity, and is streamlined in shape. ~ Stability Snags are involved in the normal erosion and ~Nature of land adjacent deposition processes that result in channels to the river changing their shape, but these processes occur ~ Timing of restoration project whether snags are present or not. The actual ~ Local factors amount of erosion caused by snags is usually small. In most cases, flood height is not controlled by snags but by some other channel constriction such as a perched channel or bridge abutment. It is common for a bridge and its Riparian Land Management Technical Guidelines, approaches to be smaller than the natural Volume one: Principles of Sound Management and channel cross-section. This leads to flood water Volume two: On-ground Management Tools and Techniques being backed-up above the bridge. available from the AFFA Shopfront for $25 plus postage and handling, toll free 1800 020 157

THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION 5 RESEARCH NOTES1 THE IMPORTANCE of arge oody ebris surfaces for algal growthLWD in lowland rivers

by Simon Treadwell Large woody debris (LWD) exerts a number of using particular carbon types. Algae, particularly influences on the structure and function of diatoms — the most abundant algae found to be stream ecosystems. It accumulates to form larger growing on LWD surfaces, are an important snags and debris dams that contribute to source of high quality carbon for many inverte- hydraulic and habitat diversity, and are impor- brates living in the river (Bunn et al. 1999). tant sites for organic matter retention and Current research in Australian lowland rivers processing. They also provide a stable and is aimed at determining the importance of LWD complex substrate for colonisation and habita- as a substrate for algal colonisation, as well as tion by fish, macroinvertebrates, fungi, bacteria, investigating how much of the total algal produc- algae, mammals, reptiles and birds. For reviews tion occurring in a river is derived from algae of LWD in Australian rivers see Crook and growing on LWD surfaces. Study sites are Robertson (1999) and Treadwell et al. (1999). located on the Murray River at Albury, Barmah In lowland rivers, snags may be important Forest and Colignan near Mildura, and on the for a large amount of the carbon entering these Lower Ovens River near Wangaratta in northern rivers through primary production. Carbon is Victoria (see Figure 1). the major food source in stream ecosystems for The Murray River is a highly modified, large all organisms including bacteria, invertebrates lowland river with a fully regulated flow, elevated and fish. Carbon can enter the stream from the nutrient levels and a history of extensive desnag- riparian zone and floodplain in the form of ging.The Lower Ovens River, by contrast, is one leaves, twigs etc., or is produced in the stream of the least regulated rivers in the Murray- itself through algal production. Algae grow either Darling Basin (NECMA 1998) with very little in the water column (phytoplankton) or attached desnagging and other habitat destruction, and to surfaces (periphyton) as part of the biofilm relatively good water quality. community. Biofilms are complex organic layers The amount of algal growth, or carbon composed of algae, bacteria, fungi and detritus, produced by algae, can be determined by held together by gelatinous compounds excreted measuring changes in the dissolved oxygen by some of the organisms that grow in the concentration in the water in which the algae biofilm, this gives algal biofilms a ‘slimy’ feel. grow. Algae are plants, they photosynthesise Healthy rivers need carbon from a variety of during the day by producing oxygen and consume Figure 1: Field site locations sources since different organisms are adapted to carbon dioxide. At night the reverse occurs, and on the Ovens and Murray Rivers. they consume oxygen and produce carbon dioxide, this is called respiration. In water, the Mildura rates of production and respiration can be deter-

Murrumbidgee River mined by measuring the changes in dissolved oxygen concentration that take place during the day and night. Algal production is termed Gross NSW Primary Production (GPP) and respiration is

Murray River termed Community Respiration (CR24).

To measure GPP and CR24 by biofilm on VIC LWD, clear perspex chambers are clamped to LWD surfaces, thereby isolating an area of N Barmah Echuca biofilm and a small volume of water (see photo 0510 km Albury Wangaratta page 7). Changes in dissolved oxygen concen- Field site locations Ovens River tration due to GPP or CR24 are measured with a special probe and recorded on a datalogger.

6 THEME RESEARCH GETTING A GRIP IT’S A WRAP INFORMATION THE IMPORTANCE ofLW arge oody D ebris surfaces

3

2

1

1200 Respiration Production

800 /day P/R 2 /m 2

mgO 400

0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Figure 2: Monthly GPP, CR24 and P/R on LWD surfaces in the Ovens River (mean ± SE, n=6). Perspex chamber clamped to LWD surface for measuring GPP. Source: Treadwell (unpublished data). Photo by Simon Treadwell.

Dissolved oxygen concentration is measured in Figure 2 presents monthly GPP and CR24 for the milligrams of oxygen per litre of water. By Ovens River, and shows a distinct seasonal reala- adding up how much oxygen is produced during tionship with increased GPP corresponding with the day or consumed at night, the rate of produc- high light intensity and water temperature in tion or respiration for the area of enclosed summer and autumn. Community respiration biofilm can be calculated as milligrams of oxygen rates are similar to those for GPP and follow the produced or consumed for each metre squared same seasonal patterns. In summer and autumn,

of substrate enclosed over 24 hours (the equation GPP exceeds CR24, that is the P/R ratio is greater -2 -1 looks like this: mgO2.m d ).The ratio of produc- than one, whilst the reverse occurs in winter. tion to respiration (P/R) is useful for showing if Although not presented here, rates are similar the biofilm community being measured is a net between the Ovens River site, and Barmah and consumer or producer of oxygen. Values of P/R Colignan on the Murray. Interestingly, however, less than one indicate the community consumes GPP is generally lower at Albury. This is most more oxygen than it produces, conversely, P/R noticeable early in summer when irrigation flows values greater than one indicates the community have just commenced.The water temperature at produces more oxygen than it consumes in Albury is up to 10° lower at this time of year 24 hours. compared to the other sites and this is the most In order to calculate how much GPP occurs likely contributor to the low GPP measured in a whole section of river, the surface area of there. LWD in that section needs to be measured.This The surface area of LWD is greatest in the Note area can then be multiplied by the rates of GPP Ovens River and lowest in Murray River at This article presents some and CR24 estimated from the perspex chambers Colignan. In the Ovens River, for every one unpublished data (unless other- to give an indication of how much production in square metre of streambed there is between 0.37 wise referenced) from the an entire section of river is occurring on LWD and 0.54 m2 of LWD surface that biofilm can author’s PhD research. During surfaces. grow on. In the Murray River at Colignan, there this research the author was the is only between 0.06 and 0.08 m2 of LWD recipient of a PhD Scholarship surface for every one square metre of streambed. and capital funding from the Results A number of factors contribute to this — the Cooperative Research Centre for Moderate rates of GPP have been measured on Ovens River is in a much more natural state than Freshwater Ecology. LWD surfaces in the Ovens and Murray Rivers. the Murray River and has not been desnagged to

THEME RESEARCH GETTING A GRIP IT’S A WRAP INFORMATION 7 THE IMPORTANCE ofLW arge oody D ebris surfaces 1352 2000 744 1274 522 494 304 1178 714 974 1175 1440 100%

80%

60%

40%

20%

0% Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Figure 3: Monthly GPP on LWD (dark bars) as a percentage of total ecosystem GPP(light bars) in the Ovens River. Large woody debris are a vital component of in-stream habitat. 2 Values above bars represent total ecosystem GPP (mgO2/m /day). Source: Treadwell (unpublished data). Photo by John Koehn.

For further the same extent, also, the Ovens River is much a wide diversity of aquatic invertebrates, information narrower and, therefore, LWD surfaces make up including species that only live on wood surfaces Simon Treadwell a greater proportion of the total habitat area.The (Benke et al. 1984, Lloyd et al. 1991). These Cooperative Research Centre actual area of LWD inundated at any particular invertebrates rely on the biofilm growing on the for Freshwater Ecology time depends on the river level height. LWD surfaces for food. A decrease in the Department of Based on estimates of total primary produc- amount of wood available for invertebrates and Biological Sciences tion and respiration for the entire river reach algae to grow on, or a decline in the optimal Monash University, at each site, it is possible to determine the growth conditions for algae, will impact on the Clayton VIC 3168 percentage of the total that is contributed by algae food supply to invertebrates and other animals Tel: (03) 9905 5640 growing on snags. At this stage, this has only been that feed on these invertebrates, such as native Fax: (03) 9905 5613 calculated for the Ovens River (see Figure 3). fish. For more information about this important Email: simon.treadwell@sci. These results show that during the late summer area of research, check out the references below monash.edu.au and autumn, high algal growth on snags or contact Simon Treadwell direct. contributes between 10% and 20% of the total instream production, this falls to less than 1% in References winter. In the Ovens River, the late summer/ Benke, A.C., Van Arsdall, T.C.J., Gillespie, D.M. and Parrish, F.K. 1984, autumn period coincides with low flows, high ‘Invertebrate productivity in a subtropical blackwater river: the importance water temperature and low turbidity. These of habitat and life history’, Ecological Monographs, no. 54, pp. 25–63. conditions combine to maximise the amount of Bunn, S., Davies, P., Negus, P. and Treadwell, S. 1999, ‘Aquatic food webs’, algal growth on LWD surfaces. By contrast, in the in S. Lovett and P. Price (eds), Riparian Land Management Technical Murray River, this period coincides with high Guidelines, Volume one: Principles of Sound Management, LWRRDC, water levels due to irrigation flows, and prelimi- Canberra, pp. 25–36. nary analysis suggest that the contribution algal Crook, D. and Robertson, A. 1999, ‘Relationships between riverine fish and woody debris: implications for lowland rivers’, Marine and Freshwater growth on LWD surfaces makes to total instream Research, no. 50, pp. 941–53. production and respiration is much lower than Lloyd, L.N., Walker, K.F. and Hillman, T.J. 1991, Environmental significance that recorded in the Ovens River. of snags in the River Murray, Department of Primary Industries and Historically, prior to wide scale desnagging Energy, Land and Water Resources and Research Development and regulation, conditions in the Murray River Corporation and Australian Water Research Advisory Council (Completion may have been similar to those in the Ovens Report Project 85/45). River.The modification of the Murray River has NECMA 1998, Draft Ovens Basin Water Quality Strategy, Ovens Basin Water most likely contributed to a decline in the Quality Working Group. amount of carbon entering the river through Treadwell, S., Koehn, J. and Bunn, S. 1999, ‘Large woody debris and other primary production on LWD surfaces. Why is aquatic habitat’ in S. Lovett and P. Price (eds), Riparian Land this important? Research, both in Australia and Management Technical Guidelines, Volume one: Principles of Sound Management, LWRRDC, Canberra, pp. 79–96. overseas, has shown that LWD surfaces support

8 THEME RESEARCH GETTING A GRIP IT’S A WRAP INFORMATION Getting a grip provides short, sharp research notes that can be Getting a GRPi practically applied in day-to-day natural resources management. RE NAGGING the Murray River by John Koehn, Simon Desnagging of our river systems, especially the 2. Practical techniques identified for resnag- s Murray River, has been recognised as a major ging and fish habitat rehabilitation; Nicol, Jason Lieschke cause of habitat loss and the consequent decline 3. Snag design and practical management of native fish populations. Snags are the main options identified for individual species and form of structural habitat in lowland rivers and fish community rehabilitation; provide critical habitat for both Murray Cod 4. Cost/benefit evaluation of resnagging and and the endangered Trout Cod. A critical need alternative resnagging techniques; exists, therefore, for increased snags in many of 5. A projection model for the benefits of the waterways of south-eastern Australia, as resnagging at other sites; and additional snag habitat of an ‘appropriate’ type 6. Adoption of scientifically based on-ground will assist the survival of these populations. resnagging works in rivers providing Resnagging, where feasible and practical, is improved habitat viability for native fish increasingly becoming a national priority for the populations. rehabilitation of our native fish populations. As part of this project, a scholarship has been This project is a preliminary step in a staged awarded to Vic Hughes at the University of program leading to river rehabilitation through Canberra under the supervision of Associate resnagging. It focuses on the logistics of reintro- Professor Martin Thoms. Vic will undertake an ducing snag habitat to a large lowland river and investigation that identifies relationships between tests the general application and success of these the geomorphology and the position of snags. methods. The project seeks to answer many of The outcomes from this work will assist with the the immediate questions that arise from the identification of suitable resnagging sites. Other simple notion of resnagging a river, such as potential collaborators who may wish to under- ~ Where can new snags come from? take work on additional aspects of this project ~How do you get them? would be welcome. ~How do you shift them? This project is funded by Agriculture, ~How do you put them in? Forestry, Fisheries, Australia through the MD ~How big, how many, where, new or old, at 2001 Fish Rehab program and is due to be what cost? completed by December 2001. Additional The project is aiming to achieve the following funding to conduct an evaluation of the environ- outcomes mental outcomes of the project is being funded 1. An objective basis for assessing the need for, by the Murray-Darling Basin Commission. and probable response to, river rehabilitation through resnagging; Below: Snags in paddock to be placed back in the River Murray.

For further information Jason Lieschke Freshwater Ecology Arthur Rylah Institute 123 Brown Street Heidlberg VIC 3084 Tel: (03) 9450 8698 Fax: (03) 9450 8730 Email: [email protected]

Photo by Jason Lieschke.

THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION 9 RESEARCH NOTES2 SOME OBSERVATIONS on the amount and distribution of arge oody ebris in Australian streams

LargeLWD Woody Debris (LWD) is critical for the Comparing Australian studies (mostly in the Ian Rutherfurd*, Karen White, Nick Marsh and health and function of Australian streams. south-east of the continent) with those from the If you have any doubts on this point, see PNW suggests that the average loading in natural Kathryn Jerie the comprehensive review provided in the streams for both regions is between 0.1 and *CRC for Catchment Hydrology, LWRRDC Riparian Land Management Technical 0.01 m3/m2. In general, small streams are consid- University of Melbourne Guidelines (1999). Attention is now turning to ered to have higher loads of timber per unit bed how to return natural loads of LWD to streams area than larger streams (Keller and Tally 1979). as part of a rehabilitation strategy. There are However, the Australian data in Figure 1 hints already several projects to artificially return that our streams may have a similar load LWD to streams that have been cleared of LWD throughout their length (Gippel et al. 1996). As (de-snagged). Notable major projects are an you can see from Figure 1, most studies have NHT funded project on the Murray River (see concentrated on catchments smaller than Get a Grip page 9), and a project funded by the 1000 km2 so we still need to look at larger Department of Land and Water Conservation in streams to see if the downstream trend is corrob- NSW (It’s a Wrap, NSW see page 29). In these orated. Another problem with this data is that projects, large logs and log-jams will be reinstated some of it comes from streams that may in the rivers. Such artificial loading is, of course, themselves have been de-snagged. A general only a stop-gap measure in the many decades guide is that most streams that have been until restored riparian vegetation provides a surveyed will have loadings of between 0.1 and natural source of LWD. If we are going to go to 0.01 m3/m2 of timber in the active channel. This the expense of returning timber to streams, we is often expressed as an area of timber per unit should know more about natural loads and distri- area of the bed (m2/m2). bution of that timber. But what do these loadings actually look like LWRRDC funded a project to suggest some in a stream? Photos 1 and 2 (opposite) show guidelines for how much timber to put back into examples of streams with their loadings. How Australian streams. This is a summary of some then would a manager decide what load of of this work. Not surprisingly, we report that timber should be returned to a stream? They average values are of little help, and that there is could use the general volume guide above (in a huge variation in LWD loads throughout a m3/m2), or better, they could reconstruct the single catchment, let-alone across Australia. In volume from historical records, or from a this article we stress the importance of under- nearby stream that is still in good condition. standing the basic factors that control the delivery of timber to streams, and its subsequent 1 PacNW survival. Understanding these natural processes SE Australia ) on a target stream will assist managers, not only 2 0.1 /m in determining how much timber there should be 3

in a stream, but also its distribution, and its likely 0.01 survival time.

0.001 Debris loading (m

Loading and distribution 0.0001 Most research into LWD has concentrated on 0.01 0.1 1 10 100 1000 10 000 2 describing the loads and distributions of timber Catchment area (km ) in streams, and most of this has been done in the Figure 1: Loading of woody debris in volume per area of active channel Pacific NorthWest (PNW) of North America. (m 3/m 2) as a function of catchment area (taken from White, 1998a).

10 THEME RESEARCH GETTING A GRIP IT’S A WRAP INFORMATION SOME OBSERVATIONS on the amount and distribution of LW arge oody D ebris Photo 1 (above): The lower Thomson River, Gippsland. A lowland, low energy river with little local disturbance to debris. Most debris is submerged. Debris loading is 0.017 m3m–2. Photo 2 (below): Upper-Edward River, NSW. Lowland rover, low energy, with silt/clay bed. Anabranch of the River Murray, near Mathoura. No disturbance to debris or riparian vegetation. River drained at time of photography, so all woody debris is visible. At bankfull, most of the debris is submerged. Debris loading is 0.037 m3m–2. Both of these photographs were kindly provided by Dr Chris Gippel of Fluvial Systems [email protected]

Production Vegetation features • Density • Habitat • Age structure Source area • Levees Delivery Channel shape • Incised

Delivery method • Self pruning • Wind throw • Meander Hydraulic regime migration • Attrition rate Survival Termites

Transport destruction

Distribution Stream power and transport Channel size

Figure 2: A conceptual model of the loading and distribution of LWD in streams.

Whatever method is used, it is important to redistribution of the timber in the stream (see understand the natural processes that control Figure 2). In the following sections we will the supply and movement of wood through discuss this general model, and then illustrate the streams. Many factors could have changed so model with case studies from Australian streams. that the ‘natural’ load of timber will no longer survive in the channel. For example, stream LWD production velocities will have increased following The production of LWD is dependent directly de-snagging so that LWD that would have on the characteristics of vegetation that is within survived before will now be washed away. Or the influence of the stream. Although the flow regulation by dams might mean that riparian vegetation nearest to the stream is of timber will now be exposed for longer periods and will rot away. Thus, it is important to most importance, timber can be carried to the understand the general controls on timber stream from floodplains, or from high in the delivery and survival in streams. catchment by debris flows and mass-wasting. The key features of the forest that are relevant are the density of tree growth, the variety of species, and the distribution of tree sizes. A model of timber Here are some examples of controls on delivery and survival LWD production. Four key factors control the amount and ~ Some riparian forests germinate in response character of timber that we see in a stream at any to a single disturbance, producing trees of point in time. These are production of timber, similar size all along the banks. A good delivery of timber to the stream, and survival and example is River Red Gums (Eucalyptus

THEME RESEARCH GETTING A GRIP IT’S A WRAP INFORMATION 11 SOME OBSERVATIONS on the amount and distribution of L argeW oodyD ebris camaldulensis) that are germinated on the LWD source zone LWD source zone banks by a single flood. Similarly, silver wattle (Acacia dealbata) tend to germinate at the same time, mature, and fall into the stream at the same age, producing pulses of timber into streams. ~ In some landscapes, trees only grow close to the stream itself. In the arid zone this is because the stream is the only moist place the landscape (for example, Cooper Creek). Albert River (naturally incised channel) Cooper Creek (natural levees) In Tasmania, trees are often restricted to the Figure 3: Channel shape influences available source areas for LWD. Incised channels that are fully vegetated provide a banks because they are the only well drained much larger potential source of LWD than streams with natural levees. areas of the landscape. In either case, the ‘catchment area’ for LWD generation is By combining vegetation characteristics and restricted. geomorphology we find that each stream has a ~Rates of growth vary dramatically amongst defined source area (or catchment area) for riparian tree species. Silver wattles can reach timber (see examples in Figure 3). For example, maturity in less than 20 years, increasing it is common to find that the LWD source area their diameter by more than 10 mm per year. is restricted to the timber falling in from directly By contrast, Huon pine (Lagarastrobos beside the channel. An example of such as franklinii) in Tasmania increases its diameter stream would be the upper reaches of the by less than 1 mm per year. This variation Acheron river in central Victoria, where the leads to a great difference in the replacement dense myrtle beech and mountain ash forest is rates for trees that do fall into streams. impenetrable to researchers (!) let alone LWD transport. In a stream with natural levees, the net Delivery flood flow is away from the channel, and this would tend to move vegetation away from the What processes deliver timber to the stream main channel and possibly into back-channels. channel? Delivery processes can be described as In addition to the potential source area of chronic or episodic (Wallace 1984). Chronic LWD, the delivery mechanisms of LWD can processes will be occurring at some point of the vary widely between streams. The range of river most of the time (for example, tree fall) as chronic mechanisms include opposed to infrequent episodic events such as 1. Windthrow — where trees are blown into the floods or debris slides. The international litera- stream. This process is more likely where ture cites numerous processes that deliver timber there are shallow rooting depths, and a single to streams, but only a few are relevant to most row of trees along the stream bank. Australian streams that do not experience snow 2. Self pruning — some species of eucalypt, avalanches and debris torrents (see Table 1). notably River Red Gum, will shed whole LWD can basically arrive in a stream by falling limbs in times of environmental stress, in (gravity), or by being transported in by flow. thereby adding LWD to the stream, whilst Table 1: Major mechanisms delivering timber to streams. maintaining the stock of riparian vegetation (O’Connor 1992). Mechanism Description 3. Meander migration — the lateral erosion of Gravity Dead trees, or limbs fall into the stream channels results in the undermining of bankside vegetation and its subsequent entry Erosion Also gravity, but accelerated by lateral into the stream. migration of the stream undermining 4. Bed exposure — where degradation of the the trees bed of a stream exposes timber that has Floating Floods carry timber into the stream previously been buried.This is an important from back-channels or floodplains process in Australian streams where timber can survive almost indefinitely in the anaer- Bed degradation Exposure of buried timber in the bed obic conditions beneath the bed.

12 THEME RESEARCH GETTING A GRIP IT’S A WRAP INFORMATION SOME OBSERVATIONS on the amount and distribution of LD argeW oody ebris 14 Density North American trees Australian trees Hardness

12

10

8 ) and hardness (kN) 3 6

4 Density (kg/cm

2

0 illow W Red alder Sassafras ellow box Douglas fir Y Pacific yew ellow cedar Oregon ash Ribbon gum Sitka spruce Black wattle Silver wattle Y Shining gum Red ironbark Silvertop ash White spruce Incense cedar Mountain ash Bigleaf maple River red gum Balsam poplar Monteray pine Pacific silver fir Coast grey box estern hemlock Ponderosa pine estern red cedar asmanian myrtle W T W Black cotton wood Mountain grey gum Californian redwood Australian blackwood Messmate stringybark Broadleaved peppermint Figure 4: A comparison of the mechanical properties of wood (average green density and hardness) in the Pacific NW of the USA, and Australia (data taken from White, 1998).

LWD survival dominant role in the destruction of LWD, for example in dry ephemeral systems such as The LWD loading at any given time and place in Cooper Creek in western Queensland. a stream depends upon how long it takes for The transport of timber out of streams is a LWD to degrade, or to be transported out of the function of these main variables: the size, reach, or both. Both of these issues are covered density, and shape of the timber, the amount of in detail in White (1998a & b). Soft, palatable timber in the bed (that is, interaction between the species like willow degrade after only 2–3 years LWD pieces), and the power of the stream to in south-east Australian streams. Hard, unpalat- transport. It may be that Australian streams are able species like River Red Gum can last for characterised by lower transport rates than thousands of years, thanks in part to their high North American streams because our timber is density and fungal resistant tannins. Figure 4 ~ dense (that is, it is less buoyant) shows that Australian hardwoods are usually ~ strong (so that its size is maintained) much denser and stronger than typical trees in ~ and multi-branched (so that large limbs bury North America. themselves in the bed). The breakdown of LWD is also dependent Also, the low relief of catchment headwaters in on the hydrologic regime, with LWD that is Australia mean that our streams have lower constantly submerged being preserved better stream power (which is a function of discharge than LWD that constantly undergoes wetting and and slope).This would reduce the transport rate drying cycles. Microbial breakdown of hardwood of timber. It is also interesting to note that limbs species is thought to be related to the surface area of trees tend to have lower density than trunks of the timber available for microbial action. In (O’Connor 1992), so that much of the LWD high energy stream systems, trees can be smashed moving downstream in Australian streams is apart by flood debris, effectively turning one large almost certainly limbs rather than trunks. piece of LWD into several smaller pieces. This has the effect of increasing the surface area for available microbial action and, hence, increases Debris jams decomposition of LWD.The breakdown of LWD From the elements discussed so far, we are able is not just by microbial action within the channel. to establish the factors controlling LWD We have found that termites can play the loading in different natural streams. However,

THEME RESEARCH GETTING A GRIP IT’S A WRAP INFORMATION 13 SOME OBSERVATIONS on the amount and distribution of LW arge oody D ebris 100 flow. The difference in the number of LWD jams in Figure 5 is a function of the ratio of 80 channel to tree dimensions. The width of the 60 Acheron River is considerably less than the

40 average height of the riparian zone, therefore, even with sufficient energy, the stream is unable 20 to transport debris because it is effectively 0 anchored by the streamside vegetation. In the Percentage of LWD pieces in log jam Percentage of LWD Cooper Creek Albert River Edward River Archeron River case of Cooper Creek, the main channel is wide Figure 5: Distribution of LWD: in relation to the height of the riparian vegeta- Percentage of LWD pieces that are part of log jams. tion, however, the available stream energy is not sufficient to transport LWD. This means that from an instream habitat perspective, the value log jams occur rarely in the Cooper Creek of LWD is not simply defined by loading, but system. by how the LWD is distributed in the channel, and its influence on the stream morphology. The distribution or ‘clumpiness’ of LWD can Some examples of be illustrated by considering how much of it occurs as single LWD pieces and how much as controls on LWD loading log jams (Figure 5). The clumpiness of LWD We have gathered data from four streams in can be described in terms of the available Australia to quantitatively assess the general energy to transport LWD and of the mobility of model described in Figure 2. Table 2 describes the debris in the stream channel. In the case of the four streams, and Figure 6 compares their the Albert River, the stream has a stream power LWD loading. In the next section we will briefly when flowing bankfull more than sufficient for explain the dominant controls on LWD loading transporting LWD.The Acheron River also has in each of these streams as an example of the sufficient energy for transporting LWD at high application of the conceptual model.

0.07 90 35 0.25 80 0.06 30 )

) 0.20 /tree) 3

2 70 2 )

2 0.05 25 60 /m

3 0.15 0.04 50 20 40 0.03 15 0.10 30 WD load (m L 0.02 10 verage log volume (m Sutream power (W/m 20 A 0.05 0.01 10 5 Spacing of riparian trees (m 0 0 0 0 Cooper Albert Acheron Edwards Cooper Albert Acheron Edwards Cooper Albert Acheron Edwards Cooper Albert Acheron Edwards Creek River River River Creek River River River Creek River River River Creek River River River Figure 6: LWD load for four Australian streams, with some average figures for important variables controlling the LWD load (stream power, spacing of riparian trees [measured over 40 m x 80 m quadrants], and average log volumes). Note that all values are averages over several stream reaches.

River Where is it? Characteristics Acheron River Central Victoria 500km2 catchment with upper reaches dominated by Myrtle Beech and Mountain Ash forest, lower reaches dominated by River Red Gum and some acacia species Edward River Southern New South Wales Secondary channel of the River Murray, flowing though extensive River Red Gum forest in the Barmah forest area Albert River South East Queensland High energy, naturally incised stream, with riparian vegetation dominated by eucalypts and rainforest species Cooper Creek South Western Queensland Low energy, distributary channel system, with riparian vegetation dominated by Coolibah.

Table 2: Four streams used to source LWD data for the model development.

14 THEME RESEARCH GETTING A GRIP IT’S A WRAP INFORMATION SOME OBSERVATIONS on the amount and distribution of LW arge oody D ebris Cooper Creek LWD volumes in Cooper Creek are very low because of low supply rates, small source areas, and high breakdown rates, and low stream power. Trees can only get into the stream by falling in from the crest of the natural levee directly adjacent to the bank. There is little evidence of trees being undermined by bank erosion. Nearly 90% of LWD in the stream were limbs of Eucalypts that had fallen directly into the channel. Limbs that fall on the floodplain tend to be carried away from the channel rather than toward it. The limbs that do arrive in the channel are eaten by termites within years, and the low stream power of the stream means that few of the limbs are transported downstream. The result is a stream with low LWD loads, with most snags lying high on the banks, and with log few jams (see Photo 3). Photo 3: A branch of the anabranching Cooper Creek system showing low LWD volumes, and dense riparian vegetation.

Albert River In contrast to the Cooper Creek, the Albert River has high stream power, and a consistent supply of large logs to the stream. The channel is deeply incised and densely vegetated. All of the trees growing on the >15m high banks can fall into the bed of the river.The river is also able to transport the moderate sized logs delivered to it. The result is a high LWD load, and a large proportion of the logs in jams (see Photo 4).

Edwards River The Edwards River has a high LWD load, possibly because of bank erosion associated with high regulated flows. The River Red Gums that fall into the stream stay where they fall, and break-down slowly. The result is few log jams (see Photo 2). Photo 4: Photograph of the Albert River showing high banks, large LWD loads, and jams. Photos by Ian Rutherfurd.

Diamond Creek 1.0 Diamond Creek is a small tributary of the Yarra River near Melbourne.This stream demonstrates 0.8 ) the interaction between vegetation type and 2

/m 0.6 stream power that can control LWD distribu- 3 tions. Measures of LWD loading and stream 0.4 power at successive points down the stream suggested that reaches with high stream power 0.2 also had high loadings (Figure 7). (m Surface of LWD 0 Figure 7: LWD load versus stream power in 051015 20 25 Diamond Creek, Melbourne (data from White, 1997). Stream power (w/m2)

THEME RESEARCH GETTING A GRIP IT’S A WRAP INFORMATION 15 SOME OBSERVATIONS on the amount and distribution of L argeWD oody ebris This is contrary to the idea discussed above in which higher stream power would tend to transport timber out of a reach. The likely explana- References tion for this anomaly is that high stream power can also equate with higher Gippel, C.J., Finlayson, B.L. & O’Neill, I.C. 1996. Distribution and hydraulic bed and bank erosion rates. In this creek, the erosion undermines large significance of large woody debris in a lowland Australian River. Eucalyptus regnans trees that fall in, block the channel, and catch more Hydrobiologia, no. 318, pp. 179–94. debris. This produces log jams in the sections of stream with high stream Keller, E.A. & Tally, T. 1979. Effects of large organic debris on channel form power. We suspect that this association between high stream power and and fluvial processes in the coastal redwood environment, in D.D.a.W. Rhodes, G.P. (ed.), Adjustments of the fluvial system. Kendall/Hunt, high loading could be wide-spread in Australia where streams are gener- Dubuque, Iowa, pp. 169–97. ally unlikely to transport large Eucalypts that fall into the stream. O’Connor, N.A. 1992. Quantification of submerged wood in a lowland Australian stream system. Freshwater Biology, no. 27, pp. 387–95. Wallace, J.B. and Benke, A.C. 1984. Quantification of wood habitat in Conclusions subtropical coastal plain streams. Canadian Journal of Fish Aquatic Science, no. 43, pp. 1643–52. Average LWD loads provide little guidance for managers wishing to return White, K. 1997. The relationship between stream power and debris loading LWD to Australian streams. There is huge variation in LWD loads along in an urban and natural stream in Victoria, Australia, Research project a single stream, let alone across climatic regions of Australia. The amount thesis, University of Melbourne. (load) and distribution of LWD in streams is a function of timber produc- White, K. 1998. Comparison of the characteristics of large woody debris tion rate, delivery mechanisms, LWD breakdown rates, and stream trans- found in streams in the Pacific Northwest and Southeastern Australia, port capacity (measured by stream power). By considering each of these Honours thesis, University of Melbourne. elements, it is possible to qualitatively explain why various Australian streams have high or low LWD loads. It is also suggested that the special character of our timber and streams mean that Australian streams are likely to have higher LWD loads, and different distributions, than the average streams described in the international literature.

This two volume set is now available on A RE ABILI ATION ANUAL the website and as a printed publication. h tmfor Australian Streams Feedback from a number of people Volume One: Concepts and Planning and organisations made it clear that Volume Two: Rehabilitation Tools some still like to Rutherfurd, I., Jerie, K. and Marsh, N. 2000. Draft for Evaluation have manuals and guidelines in hard This manual is designed to help those professional managers who are accepting the challenge of rehabilitating the physical and biological copy and not just condition of Australian streams. The manual is based on an evolving accessible via the set of ideas and contains gaps in our knowledge that need to be filled. website. As a result, It is hoped that the manual will grow and mature along with the infant we have printed stream rehabilitation industry. So feedback is always welcome. A Rehabilitation Available from AFFA Shopfront for $25.00 plus postage and handling Manual for and on the web at www.rivers.gov.au and www.lwrrdc.gov.au Australian Streams. LWRRDC’S RIPARIAN LANDS PROGRAM Committed to integrating science and practical experience in ways that promote and assist the improved management of rivers and riparian lands across Australia. For details about all the terrific products available through the Riparian Lands Program see pages 33 and 34!

16 THEME RESEARCH GETTING A GRIP IT’S A WRAP INFORMATION Be a part of MAC UARIE UNIVERSITY’S Q River Styles Short Course 10–14 July 2000. Goulburn Presented by Associate Professor Gary Brierley and Ms Kirstie Fryirs

River Styles provide a catchment-framed Accreditation procedure For more geomorphic summary of river character and information behaviour. The explanatory and predictive The term River Styles™ has been trade marked, www.es.mq.edu.au/ bases of this catchment-framed approach to and as such negotiations are underway to estab- courses/RiverStyles> the analysis of River Styles, provides a lish an accreditation framework for the River rigorous physical basis for management Styles work. Through ongoing work with NSW decision making.The River Styles procedure DLWC,the following guidelines have been estab- Application forms has been applied in 14 catchments in NSW. lished for individuals applying principles from the and financial The procedure is now being applied inter- River Styles work: enquiries should be forwarded to nally within NSW DLWC. Learner Individuals who have not undertaken the River Claire Todd Course outline Styles Short Course. Macquarie Research Ltd The course will start at 9 am on Monday Macquarie University Provisional morning, and conclude at 5 pm on Friday North Ryde NSW 2109 Individuals who have successfully taken the afternoon. Emphasis will be placed on identi- Tel: (02) 9850 7261 River Styles Short Course (and passed the fication and interpretation of River Styles. Fax: (02) 9850 8128 assessment), but are yet to complete an accred- The course will provide detailed analysis Email: ited River Styles Report (approved through of Stage 1 of the River Styles procedure [email protected] Macquarie Research Limited). (Baseline Survey of River Character and Behaviour), with insights into Stage 2 Accredited River Styler For further (Assessment of River Condition). There is Individuals who have successfully taken the information on insufficient time to consider Stages 3 and 4 River Styles Short Course and have completed course content (Assessment of Recovery Potential and the an accredited River Styles Report that has been Emily Cracknell Biophysical Basis for prioritorisation of approved through Macquarie Research Limited. Macquarie University Management programs). Only then can the term River Styles be used. North Ryde NSW 2109 Tel: (02) 9850 9448 Monday Short introduction to the River Styles™ Fax: (02) 9850 8420 Procedure presented by Associate Professor Who should take the course? Email: emcrackn@laurel. Gary Brierley and Ms Kirstie Fryirs ~River rehabilitation experts ~ Those involved in water allocation strategies ocs.mq.edu.au Field trip demonstrating a range of ~ Related personnel from National and State River Styles™ close to Goulburn Government Departments (Scientific, Policy Tuesday Field assessment of various River Styles™ and Planning staff) between Goulburn and Nowra ~Environmental Officers from Local Councils Wednesday Hands on guide to air photograph interpretation ~ Biophysical consultants who work on of River Styles™ and identification of River Natural Resources Management Styles™ boundaries ~Rivercare Officers Thursday Field analysis of sites at which air photograph analysis has been performed Cost: $1600–1650 The price includes tuition, a course booklet, site Interpretation of downstream patterns of visits, venue and morning/afternoon tea. River Styles™ Friday Geomorphic assessment of river condition and assessment task Closing date for applications 10 May 2000

THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION 17 18 THEME CASE STUDY GETTING A GRIP IT’S A WRAP TIMBER THEME CASE STUDY GETTING A GRIP IT’S A WRAP TALES 19 HAVE YOUR AY in LWRRDC’s s Strategic Planning Process s ISSUES? ARE THE AY WHAT

20 THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION It’s a RAP Keeping up to datew with what is happening across Australia in the area of natural resources management is vital. This section provides States and Territories with the opportunity to ‘wrap up’ key activities, research and upcoming events. Victoria by Leanne Haupt Re-introduction of Large Woody Debris into the Snowy River at Lochend The East Gippsland Catchment Management Authority has recently re-installed some large woody debris elements into the Snowy River estuary downstream of Orbost. This reach is approximately 900 m long and is fringed with remnant rainforest vegetation that will contribute to a continuous and sustainable debris load into the river in the longer term.This work is a trial designed primarily to assess the effect of the debris reintroduction on aquatic Placing the logs along the bank with the excavator. Photo by Leanne Haupt. fauna populations. Early explorers to the region described the vegetation on the Snowy floodplain and river banks as being “jungle-like”. In 1854, Norman Wakefield commented on the abundance of “blackwood, lily pily and gnarled kanookas with ferns and creepers” in the vicinity of the Snowy floodplain.The floodplain and river has certainly changed since these observations were made, with de-snagging of the lower Snowy River a key factor in degradation of the river and loss of biodiversity.This section of the river was first de- snagged in 1880 to allow passage of barges upstream. This phase of de-snagging continued for most of the lifetime of the Orbost Shipping Company (1880–1915). De-snagging continued intermittently into the 1930s and beyond. Final location of the debris at Lochend. Photo by Leanne Haupt. In the current trial, single logs approximately 300 mm in diameter and 12 m long were and the logs inserted at a similar angle upstream For further inserted into the river at 10 m intervals using a in the lower section. A short transition section information barge mounted excavator. This spacing was placed logs nearly perpendicular to the flow, Leanne Haupt selected following observations of photographs thereby linking the upper and lower sections.The Assistant Catchment Engineer of large woody debris previously existing in the Orbost Angling Club and Native Fish Australia East Gippsland Catchment nearby Bemm River in the 1880s, as well as are both assisting the East Gippsland Catchment Management Authority through consultation with large woody debris Management Authority in monitoring fish PO Box 1012 experts and an extensive literature review. populations in the vicinity of the trial works Bairnsdale VIC 3875 The trial reach was divided into two sections, throughout the next year. RipRap will keep you Tel: (03) 5153 0462 with logs inserted approximately 30° to the bank update you on the results of this interesting Email: [email protected] in a downstream direction in the upper section, project.

THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION 21 Queensland by Sally Boon Learning about restoration using Large Woody Debris A three-day workshop in Kenilworth involved a keen and energetic group of river practitioners and managers learning about, and developing stream management options using large/coarse woody debris (LWD). The workshop was conducted by Scott Babakaiff (see RipRap, Edition 13, 1999), and concentrated on woody debris issues including re-introduction, place- ment, requirements of restoration designs and potential for use as fish habitat, scour inducers and bank protection. The workshop was organised and supported Scott Babakaiff (course instructor) and Amos Sarabar (DNR officer, Gympie) take in the views of Obi Obi Creek. by the Mary River Catchment Coordinating Committee and was attended by Department of Technical application of workshop For further Natural Resources staff, Landcare representa- One of the outcomes of the workshop was the information tives, RiverReach staff, Maroochy Council identification of good sites for utilising LWD. Sally Boon representatives and Consultants. About twenty Ideal conditions exist where Riverine Management participants were on hand to absorb some new ~ the bankfull width is 10–30 m (no greater Qld Department of techniques to address the LWD depletion than 50 m if the placement is for geomorphic Natural Resources problem in our streams. Field investigations reasons, but up to 50 m may be appropriate GPO Box 2454 centred on Obi Obi Creek, a tributary of the if placement is purely for habitat enhance- Brisbane QLD 4001 Mary River. ment); Tel: (07) 3224 2394 The obligatory getting-to-know each other ~ the reach is not in really good condition and Fax: (07) 3224 8359 (and getting-to-know the stream) canoe paddle not completely degraded. The works should Email: down Obi Obi Creek ended with some bruised not degrade a good site due to construction [email protected] and be-draggled bodies, but all agreed there was of access tracks etc; and no better way to see the creek and its riparian ~ the final design combines the talents of a zone. While some chose to examine bed geomorphologist, a fish biologist and a sediment from under water, others realised that riparian vegetation expert. protection from an electric fence with a metal Engineered log jams involve a structure which paddle was not the most intelligent option!! covers only a proportion of the channel and is not, The theory and practical sessions covered in fact a complete ‘jam’. Just one structure may issues such as fluvial geomorphology in Australia, be able to address bank erosion, loss of woody rehabilitation efforts in Australia and overseas, debris habitat and also induce useful scour. In various restoration techniques, engineered log Australia, the types of engineered log jams shown jams, information requirements for LWD in Figure 1 may be particularly useful where re-introduction, information collection methods ~ bank heights are not too large; to undertake works and planning, and calcula- ~ re-introduction of woody debris would be tions of a potential site for suitability of works. beneficial;

Erosion and lack of LWD are evident in the Mary River system where the endangered Mary River Cod resides. All photos by Sally Boon.

22 THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION We estimated the scour (that could potentially be caused by inserting an engineered log jam) by finding the deepest pool and adding 1 m. In Obi Obi Creek, the deepest pool depth was 2.1 m (minus the riffle depth of 0.0 m), as a result, the 80% of bankfull height plus 3 m below riffle Flow meant the engineered log jam would need to be approximately 6 m high. Unfortunately, these calculations indicated that the amount of funds available would not be adequate to construct the required 6 m high log jam. The alternative ABcurrently being explored is to add a woody debris structure for habitat value at a nearby site. Figure 1: Illustrations of a) single LWD, and b) multiple LWD structures (D’Aoust and Miller, 1999). In summary Further reading ~ care is taken that thalweg deflection will not I found this workshop one of the most worthwhile Abbe, T.B., Montgomery, D.R. & cause downstream erosion; and informative I have been to. It was applicable Petroff, C. 199, ‘Design of stable ~ sediment is available to be trapped, and to South-East Queensland and I would suggest it in-channel wood debris structures downstream will not become degraded from would have been relevant to any area that has for bank protection and habitat the short term sediment decrease; experienced de-snagging or exhibits a lack of restoration: an example from ~ the structures occupy less than 10% of the woody debris within the river systems. Scott was the Cowlitz River, WA’, in S.S.Y. a highly informative and entertaining presenter Wang, E.J. Langendoen and F.D. bankfull area; and Shields, Jr (eds), Proceedings of ~ the cause of any erosion is understood and who successfully kept the audience enthralled and the Conference on Management considered during design development. wanting to learn more, even at the end of the third of Landscapes Disturbed by day! He has a good understanding of the Channel Incision, 1997. Australian landscape and its geomorphology Outcomes D’Aoust, S.G. and Millar, R.G. 1990 (through his time with the Macquarie University ‘Large Woody Debris Fish Habitat The workshop investigated constructing an crew and LWRRDC) and experience with Structure Performance and engineered log jam to add woody debris for planning for and introducing large woody debris. Ballasting Requirements’, habitat value as well as to address bank erosion. Watershed Restoration For many of us, maintaining and replacing Design velocity, bankfull depth, slope, D90 and Management Report No. 8, woody debris is a management issue. The infor- British Columbia Watershed Mannings ‘n’ were calculated to help estimate the mation provided by this workshop is invaluable, Restoration Program, 1999. amount (weight) of ballast required to secure the especially for systems like the Mary River where structure (see below for definitions). The height endangered species (Mary River Cod and Mary of the proposed structure needed to be 0.8 of the River Turtle) rely on woody debris for survival bank height, with stable structures needing to and where stream bank erosion is present also. have length to bankfull width ratios of <0.25 and Balancing the replacement of woody debris with structure height to bankfull height ratios of <0.8 erosion control is imperative, and this workshop (Abbe et al. 1997). Ideally, structures should be provided answers to previously unanswered installed at or below maximum scour depth. questions.

Participants surveying the restoration reach. ~ Design velocity — velocity of flow for which structure is able to withstand ~ Bankfull depth — water depth at bankfull stage

~D90 — bed material size for which 90% of the material is finer. ~ Manning’s ‘n’ — Manning’s resistance coefficient. The coefficient may range from: 0.01–0.04 for a sand bed 0.02–0.07 for a gravel cobble-bed 0.03–0.2 for a boulder bed ~ Slope — the water surface slope of the reach (often the bed slope is used as a surrogate for this value as the water surface slope is difficult to measure). DEFINITIONS

THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION 23 Tasmania by Martin Read LWD in Tasmania – research and Rivercare Large woody debris (LWD) provides important Willow LWD is thought to breakdown habitat in Tasmanian rivers. Many native fish quickly, be structurally simple and contribute species use LWD, for example, the river blackfish less LWD to rivers than native woody species. (Gadopsis marmoratus) which spawns inside This means that willow LWD is unlikely to form hollow logs in spring or early summer and uses long term habitat for aquatic fauna. The main LWD piles as important cover, and the Giant focus of this article is to outline the outcomes of Freshwater Lobster (Astacopsis gouldi), which is a project examining LWD funded by LWRRDC, listed under both Commonwealth and Tasmanian as well as to describe the extension of this infor- threatened species legislation. mation through advice given to Rivercare groups While these two species are well known for in Tasmania. The outcomes of the project will their dependence on LWD habitat, little is known be particularly useful for community groups about how other animals use LWD; the input of carrying out willow removal and river rehabilita- LWD from different types of riparian vegetation tion as part of many NHT projects currently to rivers; and, the use of different wood types by taking place in the state (see Photo 1). aquatic fauna. This is particularly important in Tasmania, where many lowland rivers are Research dominated by willows. The study focused on three areas 1. To explore relationships between different types of riparian vegetation and in-stream LWD across a wide variety of sites. 2. To compare benthic (bottom dwelling) invertebrate populations to LWD inverte- brate populations. 3. To investigate the influence of LWD and different types of riparian vegetation (temperate rainforest, willow monoculture and grass banks) on macroinvertebrates and fish populations on two rivers that had both willow and native LWD.

Photo 1: A willow removal site on the Clyde River. Photo by Martin Read. 1. Relationship between riparian vegetation and in-stream LWD A census of large woody debris standing stocks in 142 reaches on Tasmanian rivers was undertaken, and revealed that rivers adjacent to rainforest vegetation have the highest standing stock of LWD (see Photo 2) across a spectrum of riparian types. Removal of woody native vegetation in concert with active removal of instream LWD accounts for lower wood loadings in the rivers surveyed. Overall wood in advanced decay classes was twice as numerous than other decay classes (see Figure 1). Riparian vegetation type was important in explaining wood standing stocks, although distance from source and elevation were also important predictors of LWD volumes. Most of Photo 2: A west coast Tasmanian river with a high LWD standing stock. Photo by Martin Read. this was attributable to higher standing stocks in

24 THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION 700 (a) 6 (b) 7 600 500 6 5 400

density 5 300 e log axon number Frequency T 200 4 4 100

0 3 3 1 2345 Native Willow Native Willow (low) Decay class (advanced) Figure 1: Frequency of decay classes of all LWD surveyed. Figure 2: Measures of invertebrate density and diversity on native and willow

wood in willowed reaches: (a) Number of taxa; (b) Logedensity of individuals. rivers adjacent to rainforest compared to volumes provided important habitat for fish populations For further in all other types of riparian vegetation. It appears surveyed, with reduced or negligible standing information that the removal of vegetation for forestry or stocks of LWD corresponding to a reduction in Martin Read for agricultural development, combined with the number and size of particular fish species. Department of “de-snagging”, has reduced the quantity and, Primary Industries, hence, the availability of LWD in the downstream 3b. Effect of riparian vegetation Water and Environment portions of the catchments studied.The replace- Macroinvertebrate community composition was GPO Box 192B ment of eucalypts by willows in lower catchments different under native rainforest, willow and Hobart TAS 7001 does not appear to provide LWD of comparable grass reaches. Native LWD in native reaches Tel: (03) 6233 3195 quality with eucalypt material. were associated with a distinctive xylophagous Fax: (03) 6233 6881 fauna (mostly elmid beetles) and predatory taxa. Email [email protected] 2. Differences between benthic and Native LWD in willowed and grass reaches were wood dwelling macroinvertebrates more commonly associated with a suite of taxa Macroinvertebrate community composition of and a diversity of feeding modes, although benthic habitats was highly dissimilar from that macroinvertebrates that filter particles and of woody substrates. Native woody debris scrape algae for food showed a stronger associa- appears to support a distinctive xylophagous tion with native LWD than other feeding groups. (wood eating) taxa in comparison to benthic The association of scraping taxa in the grass substrates (riverbeds) that support a more gener- reaches may reflect the greater supply of algae on alised macroinvertebrate fauna.This emphasises wood substrates in an unshaded environment. that LWD is an important and distinctive habitat Native LWD in willowed reaches supported a in rivers. more generalised fauna that reflected the prefer- ences of particular macroinvertebrates to process 3a. Effects of wood type organic matter. Higher amounts of organic Willow LWD was uncommon in the rivers matter would be expected to be in greater supply studied and was found to be a poor ecological under willowed vegetation.These results indicate substitute for the more complex native debris that riparian vegetation type has an important which supported higher densities and richness of influence on macroinvertebrate community macroinvertebrate taxa than willow wood (see composition on LWD in the river studied. Figure 2). However, both wood types supported This study reinforces findings elsewhere that similar community composition. This indicates LWD is a major and important habitat for that in the rivers surveyed, native LWD may be macroinvertebrates and fish. LWD supports a a preferred habitat for many macroinvertebrate distinctive fauna compared to benthic or river taxa compared to willow wood, although a lack bed habitats, and in reaches bordered by native of difference in macroinvertebrate diversity and vegetation provides unique habitat for wood community composition indicates that the same eating fauna. suite of taxa use both wood types. LWD also continued page 28

THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION 25 WAestern ustralia by Bill Till Large Woody Debris demonstration site on the Dandalup River, WA Background The rivers of the Swan Coastal Plain, on which area as “an ecological desert”.This prompted the the City of Perth is located, are very different idea for the Water and Rivers Commission to from those that existed about 200 years ago. In seek funding from LWRRDC to investigate “the their original state they were sandy bedded, importance of large woody debris in sandy bed heavily vegetated and loaded with woody debris. river systems”. Funding was granted and the Today, much of the native riparian vegetation project commenced in the 97/98 Summer. that once grew along them has been cleared, along with most of the native vegetation of the Project description coastal plain. In addition, the majority of rivers The objectives of the project are in the region were extensively de-snagged early 1. To develop techniques for the replacement in the last century to the extent that little large and placement of large woody debris in woody debris (LWD) remains in the channels. The importance of LWD for flora and fauna sandy river channels. habitat is becoming well recognised. As a result 2. To monitor the ecological response to the of the activities outlined above, there has been a replacement of large woody debris in sandy large increase in the amount of unstable sandy river channels. bed habitat in the rivers of the Swan Coastal Two reaches of the river were selected for the Plain, with the high flows in winter leaving project. the river channels almost devoid of fauna. ~A Demonstration Site in a highly degraded Additionally, the lack of LWD has reduced the section of the Dandalup River 2 km frequency and depth of pools, which are typically upstream of its confluence with the Murray a refuge for aquatic fauna over the long hot River. This site, which covers a distance of summer. 500 m and is located immediately upstream Both major branches of the Dandalup River of the Paterson Road Bridge is unfenced and have been dammed for Perth’s drinking water subject to livestock grazing and trampling. supply. As part of the environmental studies for ~A Reference Site located a further 6 km the North Dandalup Dam completed in 1995, upstream on the South Dandalup River Dr Peter Davies from the University of WA within Fairbridge Farm. This site has good noted the lack of instream habitat in the lower regeneration of riparian vegetation and the reaches of the river. In fact, he has described the river has been fenced off in recent years.

Paterson Road Site Plan. LWD project site enhancement works Jan–Feb 1999

26 THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION Fairbridge Farm, once an orphanage, is now owned by ALCOA and the former Farm School buildings are leased back to Fairbridge Western Australia Incorporated. The village and farm are being developed to demonstrate best management practices for coastal plain farming and, just as impor- tantly, as a focus for youth activity, assisting young people and other visitors to learn about the environment and sustainable farming. Both sites had been sampled to measure habitat diversity using fish and macroinvertebrates, as part of previous environmental studies. The Paterson Road site was established in May 1998, with the placement of 40 large tree trunks (some still including the butt) using an Fairbridge site log riffle. hydraulic excavator. At three locations (as shown on the plan, page 26) two logs were placed perpendicular to the flow to form riffles. One very large trunk was placed mid-channel about 470 m upstream of the bridge. All other logs were placed as toe protection either immediately upstream or downstream of the riffles, or on the outside of meander bends. During the 1998 winter, which produced one major bankfull flow, several logs were moved downstream, with two lodged under the Paterson Road Bridge. These logs were the ones located on the outside of meander bends.The logs in the three perpendicular riffles remained in position. Scour holes had developed under and immedi- ately downstream of these riffles. In February 1999, the logs which had moved Logs pinned against bank. were repositioned, an additional 12 logs were placed in the reach, and 4.5 m long pine logs were ‘jetted’ into the bed to secure the logs placed on the outside of bends. No significant movement of logs were observed during the 1999 winter, however, peak flows were much lower than in 1998. The Fairbridge site was established in March 1999 over a 300 m reach immediately down- stream of a demonstration cattle crossing. As the riparian vegetation is well established in this reach, it was not possible to use mechanical equipment to position the logs. As a result, the site was established through the Fairbridge “Ecohouse Project”. Ten Landcare trainees manually dragged the logs into position and secured them. Thirty logs of somewhat smaller size than at Paterson Road were also positioned. Log riffle C. All photos by Bill Till.

THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION 27 WAestern ustralia continued The logs were retained using pine logs and Installing logs at Fairbridge site. galvanised “fencing droppers” jetted or driven Photo by Bill Till. into the bed. Sedges and rushes were also trans- planted and brushing installed to protect banks from undercutting. Some minor movement of logs, those partially secured by pine logs, occurred during the 1999 winter.This was easily rectified.

Monitoring A photographic record is the primary method of monitoring the stability of the woody debris that has been placed in the channel. Peter Davies is in November (spring) compared to February undertaking the ecological monitoring for this (summer). The loads of LWD appear insuffi- project. Three sampling surveys have been cient to create enough diversity of hydraulic undertaken; in November 1997 (prior to LWD habitats during high flow periods. However, installation), February 1999 (after LWD instal- these initial results may be indicative of the lation) and November 1999. benefits of increased LWD during the long An increase in fish diversity is the initial periods of low flow experienced during the consequence of the LWD installation, with the summer in the south west of Western Australia. number of fish species recorded increasing Further monitoring will be undertaken to substantially, from one in 1997 to six in 1999. more accurately determine the response of these The macroinvertebrate response has been more sites to the presence of the LWD. difficult to interpret. At the Paterson Road site, whilst there was a significant response to the For further information LWD measured in February 1999 (species Bill Till identified increased from 42 to 52) this was not Supervising Engineer, Waters and Rivers Commission sustained in the November 1999 sampling. This PO Box 6740, East Perth WA 6892 reduction in biodiversity has been attributed to Tel: (08) 9278 0561 Fax: (08) 9420 3176 seasonal differences caused by higher river flows Email: [email protected]

Tasmania continued Summary Given the low standing stock of LWD found by Rivercare the research study in developed areas, it seems The Rivercare Program in Tasmania provides holistic advice essential that pro-active introduction of LWD to community groups from areas of aquatic ecology, water into rivers with appropriate ecological and quality, geomorphology, riparian vegetation and river hydrological guidelines complement many of the engineering. Aquatic ecology advice includes site specific riparian vegetation restoration activities currently taking place in catchments around the country. recommendations on issues associated with LWD. Technical Restoration and replanting of native riparian advice is provided by the Department of Primary Industries, vegetation should include a dual focus of reintro- Water and Environment and the Inland Fisheries Commission ducing dead wood into channels to increase on issues related to aquatic habitat and LWD to groups in-stream habitat, and planting a variety of working on river rehabilitation. Such issues include the Australian native wood species to provide a continual source of natural recruitment of LWD retention of LWD in reaches where work is planned, the into rivers in the long term. These issues are reintroduction of LWD into reaches where appropriate, and currently being tackled in Tasmania as part of the the provision of LWD for fish habitat. Rivercare Program.

28 THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION New SW outh ales by Sarah McGirr Scientific research into the effects of LWD reintroduction in NSW rivers New South Wales has had a history of snag and development, and establishment of For general management primarily focussed on removal of monitoring methodology. Phase Two will information woody debris for flood mitigation, increasing commence in May 2000, expanding the study Sarah McGirr channel capacity for irrigation purposes, and to into two other tributaries of the Hunter River Sustainable Water improve navigation in our waterways. With the — the Allyn River and Wollombi Brook.This is Management reduced roughness, many channels have under- the major construction and experimental phase Department of Land gone bed incision, channel widening, increased of the study, which is being jointly funded by & Water Conservation sediment loads and loss of pools. LWRRDC, DLWC, HCMT, and Macquarie GPO Box 3720 Whilst the practice of de-snagging in NSW University. The study will test the efficacy of Parramatta NSW 2124 rivers has for the most part ceased, river structures in both sand and gravel-bed rivers, Tel: (02) 9895 7974 managers are reticent to launch into campaigns and will trial structures at two scales of Fax: (02) 9895 7845 to reinstate log jams and use woody debris in complexity: Email: river rehabilitation. Recent research in Australia 1. highly engineered structures intended as [email protected] and overseas has illustrated the effect of LWD on alternatives to traditional rock-based river or for information morphologic processes and biological responses engineering works; and on field trials and in natural systems. However, we still require 2. low tech structures that can be constructed demonstration sites detailed information (through experimental relatively cheaply by community based groups, research and field trials) to assess the impact of for a range of river rehabilitation purposes. Allan Raine LWD when introduced back into highly Following construction and preliminary Department of Land disturbed channels. monitoring, it is intended that the experimental & Water Conservation PO Box 2213 Such research is currently underway on the sites will act as demonstration sites for current Dangar NSW 2309 Williams River, a north-eastern tributary of the and future river managers. It is hoped that the Tel: (02) 4929 9840 Hunter Catchment, Mid North Coast NSW. research findings provide NSW with some scien- Fax: (02) 4929 6364 Phase One of the study funded by the tific rigour for an otherwise untested river Email: Department of Land and Water Conservation rehabilitation practice. Basic design guidelines [email protected] (DLWC), Hunter Catchment Management Trust (including monitoring/maintenance require- (HCMT) and Macquarie University, commenced ments) for LWD prescriptions will allow NSW and in October 1999. The experiment aims to assess river managers to make more informed and Dr Andrew Brooks the efficacy of LWD structures in river rehabilita- scientifically-grounded decisions related to both Department of tion, by recording and documenting geomorphic snag management and the implementation of Physical Geography and ecological responses to the placement of river rehabilitation techniques. Macquarie University wood at specific sites. North Ryde NSW 2113 The study team consists of researchers and Further reading Tel: (02) 9850 8318 practitioners in geomorphology, river ecology Brooks, A., Babakaiff, S., Gippel, C. & Abbe, T. 1999, Williams River LWD Fax: (02) 9850 8420 and environmental engineering including Reintroduction Project, Draft Interim Report, Outcomes of workshop held Email: Dr Andrew Brooks (Macquarie University, 18–28 October 1999, Tocal, NSW. [email protected] Sydney), Allan Raine (DLWC, Hunter Region), Dr Chris Gippel (Fluvial Systems, Victoria), Scott Babakaiff (consultant, Canada) and Dr Tim Abbe (consultant, USA). The main objective of the research and rehabilitation works is ‘to establish a long-term monitoring project which aims to evaluate the geomorphic and ecological effects of LWD re-introduction, and to develop a preliminary methodology for the design and monitoring of LWD structures’ (Brooks et al. 1999). The first phase of the project focused on the site selection, structure, prescription design Riffle incision in the Williams study site as a result of desnagging.

THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION 29 ACTustralian apital erritory by Jenny Gilles Wetlands — rehabilitating urbanised Sullivans Creek Who ever would have thought that there was any Group was successful in their 1998/99 Natural hope to restore an urban concrete lined creek in Heritage Trust application and received funds to the inner city suburbs of Canberra? Sullivans employ a Coordinator to write a Catchment Creek Catchment Group did — and believe it or Management Plan.The first version of this Plan not, it is happening! Sullivans Creek Catchment is nearly complete and the demonstration Group have produced preliminary plans for a wetlands will be the first on-ground project to demonstration wetland project in the O’Connor begin the implementation of the Plan. The sub-catchment, in the ACT. This project upstream wetland will be located adjacent to involves the construction of two urban wetlands Banksia Street, and the downstream wetland adjacent to the tributary channel that drains the next to David Street, two major streets in the residential suburb of O’Connor, along with suburb of O’Connor. Both wetlands will be Black Mountain and O’Connor Ridge Nature developed on the ‘urban open space’ of the creek Parks. Not only is there unanimous support for corridor, managed by Canberra Urban Parks the project from key scientists, community and Places (Department of Urban Sevices). groups and relevant government agencies that The wetland developments will attenuate the advise Sullivans Creek Catchment Group, but flow in the O’Connor tributary, creating a the Group has also sourced $165,000 from the 5–7 day detention period of water in the corporate sector to fund the construction of one wetlands. In addition to the Banksia Street of the wetland developments. wetland, the construction of a detention basin is Sullivans Creek Catchment is located wholly also being investigated in collaboration with within the ACT, draining 5150 ha of North Planning and Land Management (Department Canberra. The Creek flows for 11 km through of Urban Services) to further detain flow to rural and urban lands directly into Lake Burley reduce the probability of flooding downstream in Griffin, the National Capital’s major water a peak flow situation. The incorporation of a feature.The rural reaches of Sullivans Creek are detention basin with a wetland significantly severely eroded in areas, and urban reaches have reduces the cost of constructing the two devel- been lined with concrete to quickly divert urban opments separately. The construction of creek- stormwater runoff away from developed areas. based detention basins may well reduce the need The community-based Sullivans Creek for costly on-site detention facilities required for Catchment Group formed out of concern for in-fill urban developments that increase the This page: The Banksia Street the health of the catchment. It took on the role runoff produced on a site. In addition to the wetland site before development. of bringing together the many stakeholder and David Street wetland, 250 m of the concrete Opposite: An impression of management groups in the catchment, to work sides of the tributary channel directly upstream the site after development. on integrating different management programs, will be broken out, battered back and planted Photos and artwork by the environment and the community. The out, with use of rock to stabilise the channel in Geoff Thomson.

30 THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION higher flows.This will also reduce flow velocities The wetland project will also dramatically For more during and after a rain event. improve the visual quality of the associated information The demonstration wetland project in the urban open spaces in the Sullivans Creek Jennie Gilles O’Connor sub-catchment will have many corridor.This boost in amenity has been proven Coordinator, Sullivans Creek benefits to the health of the catchment, the through research to increase the value of fronting Catchment Group community and to those responsible for natural properties by up to 70–100% in the ACT. It will GPO Box 1875 resource management in the ACT.The quality of also provide increased opportunity for a variety Civic ACT 2601 the water diverted through the wetlands that of recreation activities for the local community, Tel: (02) 6279 8168 enters the main channel of Sullivans Creek will such as picnic areas, educational sites and Fax: (02) 6249 5599 be improved up to 60%, increasing the quality walking paths. Email: of water downstream flowing through the Sullivans Creek Catchment Group will [email protected] Australian National University and entering encourage community participation in volun- Lake Burley Griffin. The wetlands will reduce teer planting of the wetlands with water plants, litter through the installation of associated gross edge plants, shrubs and maintenance of the pollution traps (GPTs) upstream from each wetlands in partnership with Canberra Urban wetland. Sediment and organic matter (leaves, Parks and Places. Maintenance issues include bark and grass) will be trapped in the GPTs and the removal of windblown litter and weeds wetlands, including suspended solids and associ- from the wetlands. Monitoring of the perfor- ated heavy metals, faecal coliforms and other mance of the wetlands will be undertaken by “nasties”. Nutrients (phosphorous and nitrogen) the community in collaboration with the will be absorbed by macrophytes (emergent Cooperative Research Centre for Freshwater water plants), increasing the oxygen content of Ecology, the Centre for Resource and the water, and reducing algal blooms, scums and Environmental Studies, CSIRO, Australian odours in the lower reaches of Sullivans Creek National University, Canberra University, and Lake Burley Griffin. Canberra Institute of Technology and Currently, Sullivans Creek has little biolog- Environment Protection (Department of ical value due to the concrete lining, providing Urban Services). high flow velocities, low base flows and little or Sullivans Creek Catchment Group are no habitat for aquatic and riparian species to expecting significant community support for survive. However, the implementation of the this wetland project. The wetlands have wetland project will greatly increase biodiversity significant benefits to key stakeholders in the by creating habitat for a diverse range of aquatic catchment including major improvements and riparian species of animals and plants to in on-ground environmental health. These flourish.The wetlands will bring life back into the wetland proposals form the basis of an exciting creek system! The group is expecting to see the demonstration project that may succeed in setting return of frogs, turtles, yabbies, water birds, a new benchmark for best practice urban native fish, diverse macro-invertebrate fauna and stormwater management through the installation many other animals and plants. of constructed wetlands.

THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION 31 Commonwealth 2000 National Land Care Awards Representatives of the Commonwealth Government, Landcare Australia Limited and major Australian companies presented the 2000 National Landcare Awards at a function in Melbourne in early March. Among the awards was the Natural Heritage Trust Rivercare Award that was presented to Colin and Margaret Tonkin, of Collie,Western Australia, for “making a significant contribution to the sustainable management, rehabilitation and conservation of rivers and streams in Australia”. Colin and Margaret purchased their 162 ha property, south east of Collie, with the aim of redeveloping it for cattle production. As the Tonkins developed their land and pastures and increased their stock numbers, they noticed the increasing degradation of the waterway and wetlands through cattle intrusion. There was Colin and Margaret Tonkin, recipients of the Natural Heritage Trust Rivercare Award. significant bank erosion and damage around waterholes in the riparian zone and livestock by the time it leaves. There is now negligible For further contamination of the water. Their property was turbidity in the water flowing out of the property. information also recovering from the ravages of Cyclone Alby Colin and Margaret’s hard work and enthu- Colin and Margaret Tonkin and by wildfires. Despite this, however, the siasm have increased awareness and community PO Box 729 Tonkins noticed that there was substantial regen- involvement in waterways and remnant vegeta- Collie WA 6225 eration of boronia and wildflowers on their land, tion protection in the Collie Shire.The property Tel: (08) 9734 1810 as well as a small bandicoot colony at the top is used by the Collie Land Conservation District Fax: (08) 9784 4748 border of their property. Finding these remnant Committee as a demonstration site showing the flora and fauna communities began the Tonkins advantages of managing a riparian zone within a landcare journey to rejuvenate the waterway and total farm system. It has been recently registered appreciate the value of a living stream. as a ‘Land for Wildlife’ property. Local Collie Waterways were completely fenced and Primary School students visit the property to excluded from stock, except for essential stock learn about the environment. Colin has a large crossings and limited water access points. The waterway regeneration was astounding, with total collection of hand-painted, carved wooden birds regeneration occurring within six years. They to demonstrate the local species and their part in also established a weed eradication and vermin the living ecosystem on his farm. control program in these areas. The improve- Colin and Margaret Tonkin won this year’s ment in the waterway is significant and measur- Natural Heritage Trust Rivercare Award for able. Incoming water is acidic (pH 3–4) because making a significant contribution to the sustain- of a nearby mine. However the riparian zone on able management, rehabilitation and conserva- the property allows the water to recover to pH 6 tion of rivers and streams in Australia.

32 THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION All these publications are available from Agriculture Forestry Fisheries Australia LWRRDC’s Riparian Lands Program (AFFA) Shopfront. committed to integrating science and practical experience in ways that promote and The Shopfront’s toll free assist the improved management of rivers and riparian lands across Australia number is: 1800 020 157

Riparian Land Management Technical Guidelines Volume One: Principles of Sound Management. Volume Two: On-ground Management Tools and Techniques Lovett, S. & Price, P. (eds) 1999. ISBN: 0 642 26775 8 Australia’s top scientists have come together to produce a two volume set that is based upon the findings of five years of research undertaken through LWRRDC’s Riparian Lands Program. Volume One provides information about the physical and ecological processes characteristic of riparian lands, with Volume Two providing seven guidelines covering topics that range from the control of nuisance aquatic plants to managing riparian land for terrestrial wildlife. Available from AFFA Shopfront for $25.00 plus postage and handling A Rehabilitation Manual for Australian Streams Volume One: Concepts and Planning. Volume Two: Rehabilitation Tools Rutherfurd, I., Jerie, K. and Marsh, N. 2000. Draft for Evaluation This manual is designed to help those professional managers who are accepting the challenge of rehabilitating the physical and biological condition of Australian streams. The manual is based on an evolving set of ideas and contains gaps in our knowledge that need to be filled. It is hoped that the manual will grow and mature along with the infant stream rehabilitation industry. So feedback is always welcome. Available from AFFA Shopfront for $25.00 plus postage and handling and on the web at www.rivers.gov.au and www.lwrrdc.gov.au Stream Stabilisation for Rehabilitation in North-East Queensland Kapitzke, I. et al. 1998. ISBN: 0 642 267189 This manual identifies some of the primary problems and causes of river degradation as well as treatments and management techniques. It recognises that the sustainable use of streams depends on a range of factors such as geology, hydrology, climate, ecology, sociology, culture and economics. Available from AFFA Shopfront for $25.00 plus postage and handling, accompanied by a free brochure Evaluation of the LWRRDC Rehabilitation and Management of Riparian Lands Program LWRRDC Occasional Paper No. 03/00 Virtual Consulting Group Australia Pty Ltd 2000. ISBN: 0 642 76022 5 The findings of the recent review of LWRRDC’s Riparian Lands Program provide an excellent overview of the Program’s achievements to date in research, development and communications. The review also highlights remaining knowledge gaps and provides recommendations about possible investment activities for Phase Two of the Program. Available from AFFA Shopfront for $20.00 plus postage and handling also on websites www.rivers.gov.au and www.lwrrdc.gov.au For more information and publications covering research and development activities in the area of land, water and vegetation management check out the LWRRDC website www.lwrrdc.gov.au

Riparian Management Issues Sheets 1–7 1: Managing Riparian Land. 2: Streambank Stability. 3: Water Quality. 4: River Ecosystems. 5: Land-based Ecosystems. 6: Managing Stock. 7: Managing Snags in Rivers Free set of Issues Sheets covering the key riparian management problems that landholders and catchment groups deal with on a day to day basis. These Issues Sheets have been reprinted for a third time due to popular demand and are ideal for use at workshops, field days and other catchment management activities. Available from AFFA Shopfront (postage and handling costs only). Also on the website www.rivers.gov.au RipRap LWRRDC’s Riparian Lands Management Newsletter Free quarterly newsletter that is based around a particular management theme and written in easily understood language to update policy makers, catchment groups and landholders on the most recent developments in riparian zone management.The newsletter provides information about new research, products and case studies, as well as a wrap up of what is happening around the nation in the area of riparian zone management. Available from AFFA Shopfront (postage and handling costs only). Also on the website www.rivers.gov.au To subscribe complete form on back page of newsletter or download the form from the website Rivers for the Future LWRRDC’s River Restoration & Management Program Newsletter Free quarterly newsletter with in-depth articles covering river restoration and management research and development activities. Available from AFFA Shopfront (postage and handling costs only). Also on the website www.rivers.gov.au To subscribe complete form on back page of newsletter or download the form from the website River Landscapes Poster Visually stunning poster designed to promote the message that “Together we can restore, protect and enhance our river landscapes for future generations”. Available from AFFA Shopfront, $10.00 plus postage and handling. Also on the website www.rivers.gov.au River Landscapes Brochure Compliments the River Landscapes poster and explains how we can work together to restore rivers and riparian lands across Australia. Available from AFFA Shopfront (postage and handling costs only). Also on the website www.rivers.gov.au River Landscapes Website and Website Postcard www.rivers.gov.au is the best place to go for information on LWRRDC’s research and development activities in the area of rivers and riparian lands. Loads more information and publications specific to particular projects can be found on the website. Free postcards advertising the website address are also available, they are ideal for displays and workshops and can be ordered from the AFFA Shopfront (postage and handling costs only).

For more information River Ramblers – Children’s Internet site www.rivers.gov.au about the Riparian Lands Ramble down a river and explore river and riparian management with Program contact the the next generation of managers. This interactive web based Program Coordinator educational program uses the River Landscapes poster as a base from Dr Siwan Lovett which to explain the ecological, economic, social and cultural importance of rivers and riparian zones in Australia. The material is on (02) 6257 3379 integrated into the National Curricula and uses history, creative or send an email to writing, technology and innovation to introduce and educate children [email protected] about the need to restore rivers and riparian lands across Australia. NSW AR OUTH OAST Riparian Lands f Demonstration/Evaluations c Project products Case Studies and ‘Myth Busters’ A set of five Case Studies and twelve Myth attitudes held by farmers that prevented them Buster sheets are key outputs for the final from acting on information about the need to stage of a Riparian Lands Demonstration and improve riparian land management. Many of Evaluation Project on the Far South Coast the attitudes are based on real concerns about of NSW. The project was initiated in 1996 issues such as cost, economic viability, the by the Far South Coast Catchment effectiveness of riparian fencing, and Management Committee, as part of the problems like the proliferation of weeds and LWRRDC’s National Riparian Lands pests. Whilst the concerns are real, the Management R&D Program. It has been attitudes towards technical solutions are often supported by a number of agencies, local based on incorrect assumptions or ‘myths’. organisations and individuals. Case Studies Whilst the concerns are real, the attitudes The five case studies were produced to provide simple facts and figures, combined towards technical solutions are often based with a brief explanation of what has happened at each of the demonstration sites on incorrect assumptions or ‘myths’. established for the project. Each of the case studies shows an improvement in riparian There are already plenty of technical zone condition within a few short years of guidelines on how to manage riparian land. taking remedial action. In some cases, the There are also a number of brochures and improvement has been dramatic, despite resources that explain why riparian lands are setbacks from drought and low commodity important. A review of these resources showed prices. The case studies present an inspira- that they are adequate for the NSW South tional, but realistic picture of the activities Coast — we did not need more of them. undertaken to address riparian management However, the Attitudinal Study highlighted the problems, and it is hoped that they will need to address those issues that influence motivate and assist other property owners to farmers to resist messages about the need to take on riparian restoration projects. improve riparian lands management. The The case studies have been produced in intent of the Myth Busters is to provide simple a format that should prove useful as factual arguments to help break down these brochures for interested people to pick up at critical barriers and to promote a change of field days and information stands. They are attitude towards riparian restoration. also intended to provide simple and acces- If successful, the Myth Busters should sible copy for use by editors of magazine, help to make land owners more receptive to journal and newsletter publications. the technical guidelines, information and advisory services that are available. Myth Busters The twelve Myth Buster sheets are designed For further information, and your copy of to address the main barriers to adoption the Case Studies and Myth Busters contact of improved riparian land management Don McPhee or Rosie Chapman practice. The Myth Busters arose out of the Department of Land and Water Conservation findings from a key aspect of the project, PO Box 118, Bega NSW 2550 which was an Attitudinal Study. This Study Tel: (02) 6491 6208 Fax: (02) 6492 3019 identified a number of perceptions and Email: [email protected]

THEME CASE STUDY GETTING A GRIP IT’S A WRAP INFORMATION 35 (Copies of these editions are available.) Edition 10, 1998: Streambank stability Edition 11, 1998: Riparian zones: what are they? Edition 12, 1999: Managing the riparian zone within a total farm system Edition 13, 1999: Benefiting from overseas knowledge and experience Edition 14, 1999: Managing and rehabilitating riparian vegetation RPL WRRDC’S RIPARIAN LANDSRP MANAGEMENT NEWSLETTER A COMPONENTia OF THE RIVER RESTORATION AND MANAGEMENT PROGRAM Edition 15, 1999: Seeing is believing: the value of demonstration sites

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Clip or copy ■ this coupon ☛ Would you or a colleague like to be on our mailing list and return to for RipRap or other LWRRDC newsletters? Dr Siwan Lovett, LWRRDC Program Coordinator Your name: Mr, Mrs, Ms, Dr (please circle) First name: ...... River Restoration and Riparian Lands Surname ...... Land and Water Resources R&D Corporation Position: ...... GPO Box 2182, Canberra ACT 2601 Organisation: ...... Tel: 02 6257 3379, Fax: 02 6257 3420 Postal address: ...... Email: [email protected] ...... State ...... Postcode ...... Some LWRRDC publications are available from the Tel: ...... Fax: ...... AFFA Shopfront situated in the Edmund Barton Building, Email: ...... Core 2 Entrance (off Blackall Suggest a theme for future issues: ...... Street) Barton ACT 2601 Toll free: 1800 020 157 ......

Disclaimer ■ Riparian Management Issues Sheets ☛ The information in this publication has been published Available at AFFA toll free 1800 020 157 and at www.rivers.gov.au by LWRRDC to assist public knowledge and discussion and ■ help improve the sustainable Yes! Please put me on the mailing list for management of land, water the following LWRRDC R&D newsletters: and vegetation. Where technical information ■ RipRap — Riparian Lands Management has been provided by ■ Wa terwheel — National Irrigation R&D Program or contributed by authors external to the Corporation, ■ Intersect — LWRRDC general newsletter readers should contact the ■ Focus — Dryland salinity author(s) and make their own enquiries before making ■ Rivers for the Future use of that information.